Are you using Update Manager or update it manually? if you update it manually, you have to run "eclipse -clean" once, "com.spket.extjs" seems you update from a very old version, try remove following plugins manually:

Sometimes I notice that the auto complete doesn't propose the whole list that it should be. For instance:
Ext.get(el). [Ctrl + Spacebar] just shows an incomplete list of Ext.Element functions.
It shows mostly animation functions like slideOn slideOut ..., but not others like createChild, insertSibling etc.